In the aforesaid applications there are described apparatus and methods for staging sold-vapor compounds, the descriptions of which are incorporated herein by reference.
The use of compounds comprising solid-vapor compositions formed by adsorption, sometimes referred to as absorption, of gas molecules on a solid adsorbent as heat pump working materials is known in the art. Heat pump systems using such materials have a number of advantages over other heat pumps for residential and commercial space conditioning, industrial heat pumping and refrigeration. Such advantages include higher temperature lift created by the solid-vapor media as compared to other sorption media thus eliminating the need for cooling towers or lift staging. Moreover, the apparatus used for the solid-vapor compound heat pumps require few, if any, moving parts, resulting in simple and reliable hardware. Additionally, such systems do not use the objectionable CFC's.
The solid-vapor compounds suitable for heat pumps include complex compounds which are materials which adsorb molecules of gas to form coordinative bonds in which the gaseous reactant coordinates via electron displacement with the solid adsorbent, commonly a solid metal inorganic salt. The adsorption/desorption process releases significant heat during adsorption and adsorbs energy during the desorption phase. Unlike most other sorption processes, the entire adsorption or desorption reactions may occur at constant temperature, thus eliminating problems with hot and cold sorber ends. Useful gaseous reactants include water, ammonia, methanol and the like. A number of such materials are described in U.S. Pat. Nos. 4,822,391 and 4,848,944. Such compounds and their uses described in the aforesaid patents are incorporated herein by reference.
Heat activated heat pumps consist of a heat engine subsystem which generates high pressure refrigerant vapor, essentially a thermal compressor, and a heat pump subsystem which uses high pressure refrigerant to produce cooling or heat pumping. The thermal compressor, heat pump, and their combination in a heat activated heat pump comprise useful thermodynamic systems which make advantageous use of solid-gas reactions. In the aforesaid applications there are described apparatus and methods using constant pressure staging techniques resulting in improved heat activated heat pump systems. It is an object of the present invention to use such reactions and staging techniques to even greater advantage and efficiency.